Stenotrophomonas maltophilia pericarditis

To the Editor,

Pericarditis is defined as a pericardial inflammation caused by infectious and non-infectious etiology. It may be clinically silent or may result in severe hemodynamic collapse and mortality. Developments in the field of antibiotic therapy, cardiac surgery, hemodialysis, cancer chemotherapy, and organ transplantation, as well as the current epidemic of HIV infection and AIDS, have expanded the spectrum of agents in the etiology of pericarditis and cardiac infections (1, 2). Etiology of the disease effects the outcome. Although purulent bacterial pericarditis and tuberculous pericarditis are less common, they may cause serious morbidity and mortality (1). It is essential to establish a correct diagnosis because if left untreated, the combination of tamponade and sepsis may result in up to 100% mortality. The accurate incidence of pericarditis has not yet been reported. A few reports on the antimicrobial susceptibility of common causative microorganisms of bacterial pericardial effusions have been published. In a study conducted by Sotoudeh Anvari et al. (3) in Iran, 320 patients hospitalized with pericardial effusion at Tehran Heart Center between 2007 and 2012 were prospectively examined. Bacterial cultures were positive in 35 patients. The most common pathogens were Staphylococcus epidermidis, S. auerus, and S. haemolyticus, and other causative organisms were Streptococcus spp., Enterococcus faecium, Pseudomonas aeruginosa, and Acinetobacter baumannii (3).

Stenotrophomonas maltophilia are motile, glucose non-fermentative, gram-negative aerobic bacilli. They are an infrequent cause of health care-associated infections. This paper presents a patient with underlying lung cancer who was admitted to the emergency department with complaints of dyspnea, cough, and wheezing and was diagnosed with S. maltophilia pericarditis.

A 78-year-old male patient who had lung cancer with no history of chemotherapy and radiotherapy was admitted to the emergency department with complaints of chest pain, cough, dyspnea, and wheezing. Pericardial friction was heard on cardiac auscultation. Echocardiography revealed pericardial effusion. The patient was transferred to the cardiology intensive care unit. Laboratory results were as follows: CRP level, 3.44 mg/dL; WBC count, 14.25 106/mL; and neutrophil count, 70.9%. Evaluation of the pericardial puncture fluid revealed total protein level of 4.9 g/dL, albumin level of 3.2 g/dL, LDH level of 267 U/L, and adenosine deaminase level of 33.6 U/L. Microscopy revealed 400 leukocytes/mm³. An empirical treatment with ceftriaxone 2x1 g and clarithromycin 2x500 mg was started. Massive pericardial effusion and tumor were detected in the lung and thorax by computerized tomography. Pericardial puncture fluid culture yielded non-fermentative, gram-negative bacteria identified as S. maltophilia by MALDI-TOF MS (VITEK MS, Biomerieux, France). Minimum inhibitory concentration results via gradient test (E test, Biomerieux, France) were found as sensitive for minocycline, trimethoprim/sulfamethoxazole, levofloxacin, ceftazidime, and chloramphenicol. There was no evidence of acid-resistant bacilli in mycobacterial staining and culture. Administration of i.v. levofloxacin 500 mg/day was started after consultation from the infectious diseases department. Pericardial effusion was not detected in the control echocardiography performed after 12 days. During follow-up, i.v. ceftazidime 3x2 g/day was started due to persistent fever, and the patient was transferred to an infectious disease clinic. Levofloxacin and ceftazidime were continued for 28 and 10 days, respectively, while the fever was resolving. During follow-up, the CRP level was 0.61 mg/dL and WBC count was 6.37 106/mL. The patient was discharged with a good general condition and no active complaint. No relapse occurred after 6 months of follow-up.

Bacterial pericarditis is a clinical condition that may conclude in serious consequences. Our case emphasizes the importance of bacterial culture in terms of detecting rare pathogens of pericarditis in etiology and also pathogen oriented antibiotic treatment. To our knowledge, this case is the first case of S. maltophilia associated pericarditis in the literature.